In general, in continuous casting facilities, as means for controlling outflow of a molten metal from a molten metal vessel, a slide valve device for opening and closing an outflow port of the molten metal vessel is provided at a bottom portion of the molten metal vessel.
As the slide valve device, the applicant of the present invention has invented and developed a slide valve device constructed of a fixed plate, a slide plate, and a seal plate (Patent Literature 1).
Specifically, as illustrated in FIGS. 14 and 15, a slide valve device 20 disclosed in Patent Literature 1 includes a base frame 2 for fixing a fixed plate 3, the base frame 2 being fixed to a bottom lower surface 1a of a molten metal vessel 1, a slide case 4 including a slide plate 5, the slide case 4 being positioned below the fixed plate 3, a seal case 21 including a seal plate 6 or including a seal plate 6 and a shooting nozzle 21a, the seal case 21 being positioned below the slide plate 5, and an actuator 7 for sliding the slide case 4. In the slide valve device 20, the slide case 4 and the seal case 21 are coupled to each other by coupling means 23, and the slide case 4 and the seal case 21 are integrally slid so that a surface pressure is appliable and releasable.
Further, as illustrated in FIG. 17, the slide valve device 20 includes a rotatable stopper 52 for fixing the seal case 21 situated at an arrangement location so that the seal case 21 is not moved.
As illustrated in FIG. 16, in a state in which the surface pressure is applied, the seal plate 6 is biased upward by the seal case 21 including rollers (movable members) 14 slidable on support surfaces 13 situated at side portions of the base frame including springs 12. Accordingly, the fixed plate 3, the slide plate 5, and the seal plate 6 are brought into press contact with each other with a predetermined pressing force. As a result, leakage of a molten metal and intrusion of air through nozzle holes 3a, 5a, and 6a of the respective plates 3, 5, and 6 may be prevented.